Dear all i have given a lot of tests and i am preparing for

I was exactly in your shoes few weeks ago, so I can relate fairly well. Please check my response (from today) to this thread - tomorrow-if-not-700-is-750-possible-in-4-weeks-116367-20.html#p964320

I hope this answers some of your queries.

Forget about these number all together. These number are misleading on what to focus. Take 1 step at a time, in the following order.
1. Solidify your SC strategies. (THIS IS THE MUST FOR EVERYTHING - without this, your RC can't be strong). SC tests whether you can understand the meaning of a sentence. If you can't understand the meaning of a complex sentence, it will be a tough time for you in RCs.
2. Check my post - how you can slowly improve RC. It will take time - you just need some patience.
3. CR - I would recommend follow Powerscore CR guide. Read it line by line - it will change you by the time your are done reading the book and practice all the drill in the book.

Hope this helps.

abhicoolmax is absolutely right about this point. Sentence structure is the foundation for understanding RC since RC is completely about perspective/opinion of the author. You can only understand the direction that the author takes by understanding how he/she structures the passage, through sentence structure and keywords like however, for example, etc. And from these connecting words you'll know what to read and what not to read.

Your on and off performance has to do with comfort with your approach. You seem to lose your pace when you jump from SC to CR preparation and it might be because your approach to each strategy is not solid. You need a solid attach strategy, a solid thinking process that quickly processes the question and then conquers it, rather than trying to "refigure" it out each time. You should be able to recognize the same types of questions over and over when you practice. If not, you're not making the most of your study sessions.